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The risks are sinking in. For months, discussions about fracking in California have focused mostly on public disclosure. Should people living near fracked oil and gas wells, for example, be notified about this controversial procedure, which involves blasting huge volumes of water mixed with toxic chemicals underground?

But being informed of fracking doesn't mean you'll be protected from its dangers. Now, three bills in the California Legislature have shifted the debate. Recently approved by the Assembly Natural Resources Committee, all three bills would impose a moratorium on fracking, also called hydraulic fracturing, while fracking pollution's threats to our air, water, climate and health are studied.

That's a sensible approach. This is an inherently dangerous process, and it's all the worse in California because fracking is happening without meaningful oversight by state oil and gas officials.

Fracking has been used in at least hundreds of oil and gas wells across the state, from Colusa toLos Angeles.Oil companies are clearly keen to frack large oil deposits in the Monterey Shale, a geological formation beneath scores of towns and cities and some of our most productive farmland and beautiful wild areas.

The disturbing truth, however, is that fracking could be happening almost anywhere in California where it's useful to oil and gas producers - without the public ever knowing. State oil and gas officials don't track fracking or monitor what dangerous chemicals are used in the process. And they aren't enforcing existing state laws or underground injection regulations that clearly should be applied to fracking.

State regulators did announce last year that they would draw up new fracking rules. But the initial proposal was woefully inadequate and problematic, and it could be years before regulations are in place.

That astonishing lack of oversight helps explain why state lawmakers are tackling this issue. But as the facts about fracking have become clear, many Californians are starting to feel, as I do, that even active regulation wouldn't adequately protect the state.

Modern fracking is an extremely intense industrial activity - like conventional oil and gas development on steroids - and as it's been deployed around the country the damage has been considerable. Are we going to allow the use of ever more extreme techniques to exploit California's shale oil, just when we need to transition urgently to a clean energy future to ward off climate change catastrophe? The price of obtaining this unconventional petroleum is simply not worth paying.

A fracking boom in North Dakota, for example, led to more than 1,000 spills and accidental releases of oil, wastewater and other fluids in a single year, according to an investigation of state records by the nonprofit journalism organization ProPublica.

Air pollution has also been a major problem. Colorado School of Public Health researchers found that people living near fracked wells in that state were at greater risk of asthma and other respiratory problems, as well as cancer, caused by air pollutants.

In California, we're already grappling with high childhood asthma rates and a dangerous water shortage. Fresh water is preferred for fracking, according to state officials, so where will the fresh water for a fracking boom come from?

And where will fracking water go after it's used? Increasingly, companies dispose of fracking wastewater using injection wells, which can lubricate fault lines and have been linked by geologists to destructive earthquakes in places like Prague, Okla.

Fracking also threatens mainstays of our economy, like the agriculture and tourism industries. Fracking's true price could be astronomical. In Monterey County, for example, oil companies have snapped up mineral leases not far from successful vineyards and organic farms. A fracking boom there could put jobs and businesses in jeopardy.

As these dangers become better known, momentum for a fracking ban is building. After all, protection of our air, water, wildlife and children's health is priceless. That's why California legislators increasingly support a halt to fracking. And it's why pressure is growing on Gov. Jerry Brown to stop this dangerous activity before irreversible harm is done to California's way of life.

Kassie Siegel is director of the Center for Biological Diversity's Climate Law Institute, which is based in San Francisco.